Evaluating needle-free connectors associated backflow in Midline and peripherally inserted central catheters: A top...

Area of Science:

• Vascular access devices
• Medical device safety
• Fluid dynamics in catheters

Background:

• Needle-free connectors (NFCs) are crucial for reducing needlestick injuries in vascular catheterization.
• NFCs are categorized by their fluid displacement: positive, negative, neutral, and anti-reflux.
• Different NFC types and clamping sequences may influence fluid dynamics within catheters.

Purpose of the Study:

• To evaluate the backflow volume (BV) in vascular catheters using different NFC categories.
• To compare BV across NFC types when used with peripherally inserted central catheters (PICCs) and Midline catheters (MCs).
• To assess the impact of clamping sequences on BV with various NFCs.

Main Methods:

• A bench study evaluated four NFC types with 4 Fr x 60 cm PICC and 4 Fr x 25 cm MC.
• The experimental setup simulated physiological superior vena cava blood pressure.
• Three operators performed standardized sealing sequences, and subsequent BV was measured in mm³.

Main Results:

• No NFC completely eliminated backflow into the catheter.
• Positive displacement NFCs demonstrated significantly lower BV with PICCs (0.83 mm³) compared to other NFCs.
• No significant differences in BV were observed between NFC types when used with MCs.
• Clamping sequences did not affect BV for neutral and anti-reflux NFCs.

Conclusions:

• While no NFC prevents backflow entirely, positive displacement types offer reduced reflux with PICCs.
• The choice of NFC may be critical in minimizing backflow, particularly with PICCs.
• Further research could explore optimal NFC selection and usage protocols for different catheter types.